145562216021 has 4 divisors (see below), whose sum is σ = 145563304332. Its totient is φ = 145561127712.

The previous prime is 145562216003. The next prime is 145562216027. The reversal of 145562216021 is 120612265541.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 120612265541 = 2399 ⋅50276059.

It can be written as a sum of positive squares in 2 ways, for example, as 101499588100 + 44062627921 = 318590^2 + 209911^2 .

It is a cyclic number.

It is not a de Polignac number, because 145562216021 - 2¹⁸ = 145561953877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (145562216027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 309920 + ... + 622233.

It is an arithmetic number, because the mean of its divisors is an integer number (36390826083).

Almost surely, 2^145562216021 is an apocalyptic number.

It is an amenable number.

145562216021 is a deficient number, since it is larger than the sum of its proper divisors (1088311).

145562216021 is an equidigital number, since it uses as much as digits as its factorization.

145562216021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1088310.

The product of its (nonzero) digits is 28800, while the sum is 35.

The spelling of 145562216021 in words is "one hundred forty-five billion, five hundred sixty-two million, two hundred sixteen thousand, twenty-one".